Journal of Nanoparticle Research最新文献

Presence of TiO₂ nanoparticles in aqueous surfactant solutions affects air–liquid interfacial characteristics of the system in which they have been dispersed. Foam formation, as a comprehensively applied process for new materials and techniques development, is one of the phenomena affected by changes of interfacial properties of solutions containing surfactants. Therefore, finding the relationship between interfacial properties and foamability is of a great importance for predicting and controlling the behaviours of foaming systems. Herein, using interfacial tension and zeta potential measurements, we studied air–liquid interfacial behaviours of negatively charged anatase TiO₂ nanoparticles in two types of ionic surfactant solutions, i.e. cetyltrimethylammonium bromide (CTAB) and sodium dodecyl sulphate (SDS), with their concentrations varied from 1e − 6 M to 1e − 1 M. Foamability studies of these surfactant solutions containing nanoparticles showed that the foam formation was dependent on the type and concentration of the surfactant, and the presence of TiO₂ nanoparticles affected the minimum concentration of surfactants required for the foam formation. These nanoparticles were also found to affect the size distribution of bubbles formed in the foam. In case of the CTAB solutions containing TiO₂ nanoparticles, adsorption of TiO₂ nanoparticles at the air–liquid interfaces prevented bubbles’ coalescence and thus resulted in the formation of foams with smaller bubble sizes in comparison to those of SDS solutions. These findings are important for the formulations of foam-forming materials in which the particles are often used for stabilising foams, providing insight into industrial processes where foaming characteristics need to be controlled.

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Organophosphate and organochlorine pesticides (OPPs and OCPs) have extensively been used for plant protection in agriculture. Being highly persistent and toxic, their indiscriminate use over the years has posed a severe threat to human health and ecological stability. These are labelled as hazardous classes of chemical compounds by the WHO. Though many of these pesticides are slowly phased out in most developed countries, these are still in use in most developing countries amidst a lack of stringent regulations, making it necessary to monitor their concentration levels. Complex matrix coupled with low concentration levels make pesticide monitoring quite challenging. Though sensitive and highly accurate, the currently established detection methods are time-consuming and quite expensive, rendering them inaccessible for wide-scale routine analysis. Nanomaterials (NMs), with their exceptional physicochemical properties, have emerged as promising tools for detecting OPPs and OCPs. Unusual structural manipulations in NMs lead to them exhibiting distinct electrical and optical properties. This review details the hazardous impact of some commonly used OPPs and OCPs. It explores the use of functionalized nanomaterials, including metal nanoparticles, nanozymes, nanocomposites, carbon-based nanostructures and metal–organic frameworks in their detection. The study provides a comprehensive insight into the role of nanomaterials in achieving lower detection limits up to the nanomolar range through enhanced signal responses in spectroscopic, electrochemical and optical techniques and potential for on-site analysis. Challenges associated with these methods and future directions for developing even more robust and practical nanomaterial-based sensors for organophosphate and organochlorine pesticide detection have been discussed.

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To enhance the surface properties of pressure vessels, this study utilized ultrasonic electrodeposition to prefabricate pure Ni and Ni–TiN thin films on the vessel surface using a modified Watts nickel bath. The effects of ultrasonic intensity on phase composition, surface morphology, and microstructure were analyzed through scanning electron microscopy (SEM), X-ray diffraction (XRD), transmission electron microscopy (TEM), and scanning probe microscopy (SPM). Mechanical properties, including Vickers hardness, wear resistance, and friction coefficient, were evaluated. The results indicated that the Ni–TiN thin film fabricated at 30 W/cm² displayed a smooth and uniform surface morphology, with TiN nanoparticles uniformly dispersed within the Ni matrix. This structure resulted in higher hardness (920.6 HV) and improved wear resistance (47.67 µm wear depth) compared to other films. SEM, TEM, and SPM analysis revealed that the NT30 film (synthesized at 30W/cm²) displayed an even, uniform surface morphology. The Ra and Rms values, measured over a 3.98 µm² surface area, were 23.2 nm and 35.6 nm, respectively. The average grain sizes of Ni and TiN were approximately 68.8 nm and 42.6 nm, respectively. Further, the ultrasonic intensity significantly influenced the film's performance, with the optimal intensity (30 W/cm²) achieving the best balance between film smoothness, microstructure, and mechanical properties. XRD analysis indicated that films prepared under different plating parameters displayed identical diffraction angles corresponding to the Ni phase, with variations observed only in diffraction intensity. According to microhardness analysis, the Ni and Ni-TiN films (fabricated at 30 W/cm²) showed the lowest (381.4 HV) and highest (920.6 HV) microhardness values, respectively, while wear analysis indicated the least weight loss and wear depth (approximately 47.67 µm) for the NT30 film, signifying improved wear resistance. Corrosion testing revealed that the NT30 film showed the lowest corrosion current density (I_corr = 4.8 × 10⁻⁶ A/cm²) and the most positive corrosion potential (E_corr = -0.18 V), indicating enhanced corrosion resistance compared to the Ni and NT0 films.

Silver nanoparticles (AgNPs) are increasingly recognized for their potential in biomedical and environmental applications such as antimicrobial, anticancer, and drug delivery properties. But their widespread use is a source of concern with regard to toxicity. The primary toxicological effects of AgNPs are due to oxidative stress causing cellular damage, DNA damage and mitochondrial dysfunction. The interaction of these AgNPs with cellular membranes generates reactive oxidative species (ROS) and interferes with homeostatic redox balance and induces the apoptotic pathway. AgNPs toxicity is influenced by many factors, including particle size, surface modification and synthesis method. Typically, smaller AgNPs are more toxic; however, surface modifications with biocompatible agents can reduce some of the harmful effects. Possibilities of creating AgNPs with lower toxicities using green synthesis methods through plant extracts and other natural agents are promising. However, while these developments are important, more effort is needed to fully understand how AgNPs exert their toxicity, assess various aspects of their safety and optimize their use for therapeutic or industrial purposes. Environmental impacts and a deeper knowledge of human health risks, in particular, chronic effects, are important future research areas.

Graphical Abstract

Silver nanoparticles induced cytotoxicity

Acute ischemic strokes (AIS) represent a major health concern with more than 12 million deaths per year. Despite the establishment of intravenous thrombolysis as the main line of treatment three decades ago, and the subsequent advent of endovascular therapy, most patients remain disabled. While nanomedicine has shown considerable promise in the management of strokes over the years, there remains a gap between the numerous preclinical studies and the paucity of related clinical trials. In the last five years, around 250 articles described preclinical nanomedicine-based approaches to tackle AIS. These articles explore multiple directions to alleviate AIS, including firstly neuroprotection, followed by the use of thrombolysis through various approaches. Notably, they show a broad variety in the in vivo model choice as well as key readouts, making comparison across protocols difficult. Moreover, relevant data for clinical translation is often lacking, such as biodistribution and organ toxicity, pharmacokinetics, or stability of the proposed nanomaterials. On the other hand, only a few clinical trials have involved nanoparticles, with mixed results. Thus, it can be proposed that among the obstacles hindering the clinical application of the often-promising nanomaterials, the major challenges are the insufficient characterization of nanomaterials including storage, stability, biodistribution, toxicity, and pharmacokinetics; diversity of in vivo protocols, hyper-focused ischemia–reperfusion damages compared to thrombolysis; and a necessity to acknowledge the complexity of AIS thrombi when designing a therapeutic approach. However, ongoing research considering the speed and feasibility requirements for AIS might result in future improvement in patient care.

Metal–organic frameworks (MOFs) with large active surface area have recently gained considerable attention due to their potential applications in electrochemical sensing. In this work, composites based on carbon nanotubes and bimetallic metal–organic frameworks are presented as the electrochemical platforms for the detection of emerging water contaminants, such as bisphenol A. The performance of the sensors was optimized and evaluated using differential pulse voltammetry technique. The results show an enhancement of the electrochemical output signals for the electrodes modified with Cu,Ni-BTC/CNT and Fe,Ni-BTC/CNT composites. The results have also demonstrated the important role of nickel ions which are indeed present in the samples at relatively low content (four times less than Cu and Fe ions). The detection limits of bisphenol A sensor based on Cu,Ni-BTC/CNT and Fe,Ni-BTC/CNT were 0.5 and 0.7 µM, respectively. In the same time, the morphological and structural studies have shown a better quality of crystals in Cu,Ni-BTC/CNT and a more porous structure in Fe,Ni-BTC/CNT; which might be responsible for the better sensing performances on the electrode modified with Cu,Ni-BTC/CNT. The proposed method is versatile and can be used to prepare a wide range of composites made of these bimetallic MOF structures with different additives, depending on the target applications.

This study presents the successful synthesis of bismuth vanadate (BiVO₄) using a hydrothermal method and its application as a modifier on glassy carbon electrode (GCE). Fourier-transform infrared (FTIR) spectroscopy confirmed the presence of V–O stretching vibrations, while X-ray diffraction (XRD) analysis verified a pure monoclinic BiVO₄ crystal structure. Morphological analysis revealed spherical BiVO₄ particles, which contributed to enhanced electrochemical performance when integrated into the modified GCE. BiVO₄/GCE exhibited superior electrochemical performance, as confirmed by cyclic voltammetry (CV) and differential pulse voltammetry (DPV) studies, in detecting analytes including hexacyanoferrate, tetracycline (TC), and levofloxacin (LVX). BiVO₄ modification significantly boosted the performance of the electrode in terms of sensitivity, selectivity, and electron transfer kinetics. These enhancements can be attributed to BiVO₄’s efficient electron transport and electrocatalytic activity. Notably, BiVO₄/GCE exhibited the potential for simultaneous detection of multiple antibiotics showing its versatility for diverse electrochemical sensing applications. The limits of detection (LOD) and quantification (LOQ) for TC were 27.9 µM and 83.3 µM, respectively, while for LVX, they were 7.39 µM and 22.3 µM. Overall, these findings position BiVO₄/GCE as a promising platform for advanced electrochemical detection and analysis across various fields.

Graphical Abstract

Hydroxyapatite (Hap) is a mineral extensively studied as an applied biomaterial due to its biocompatibility and physicochemical capabilities. Many methods of Hap synthesis have been developed, and multiple modifications have been proposed to improve its behaviour under different biological contexts and applications, like doping Hap with lanthanides to introduce luminescent characteristics to the material or adding molecules to interact with specific cellular receptors. The aim of this study was to synthesize a nanocrystalline Hap using an electrochemical method, also modified with a europium homogeneous doping and folic acid, as a potential applied biomaterial design. The material synthesized was extensively characterized and confirmed as a crystalline nanometric Hap, and the Eu homogeneous distribution within the nanomaterial was achieved after testing different variations of the electrochemical method. Also, folic acid (FA) modification of the material was completed via a direct interaction between the FA and the Hap-Eu surface. Hap-Eu nanoparticles synthesized were biocompatible and demonstrated luminescent properties within a cellular context, confirming its potential as an applied biomaterial. Thus, the homogeneous Eu³⁺-doped Hap nanomaterials obtained through this method of synthesis, and its FA modification, proved to be practical candidates for further research on novel and more specific biomaterials.

Graphical abstract

Alternative text: The figure shows a schematic diagram of Hap-Eu synthesis, with several images. First, a photograph of the equipment used, consisting of a power source connected to a mechanical stirrer with rotating electrodes, below them is a water bath over a magnetic stirrer plate. A second photo with a detailed view of the reaction pot inside a water bath where electrodes are shown inside the reaction solution of Ca, EDTA and phosphate; in the reaction pot Eu was added using two methods a single addition and a multiple addition. Third photo shows resulting Hap-Eu white powder and fourth photo has the Hap-Eu after folic acid modification, resulting in a yellowish powder. Bottom line of the graphical abstract shows the (Eu+Ca)/P ratio over time, the nanometric shape and the luminescent properties of the nanomaterials synthesized, and they correspond to Fig. 2d, Fig. 7a and Fig. 8b of the article respectively.

RNA is rapidly emerging as a pivotal therapeutic modality in oncology. Nonetheless, the successful delivery of RNA molecules into cells faces obstacles due to their large molecular weight, inherent negative charge, and susceptibility to degradation by RNase enzymes. In recent years, exosomes as RNA delivery vehicles have received increasing attention as an innovative approach to treat cancer. Exosomes offer distinct advantages in delivering RNA, including enhanced cellular targeting, improved stability, and reduced immunogenicity, thereby facilitating the efficient transfer of therapeutic RNA molecules into target cells. Therefore, it is crucial to summarize the applications of cancer therapy through exosome-loaded RNA. In this review, the formation process of exosomes is briefly introduced, followed by a summary of existing loading methods and a focus on therapeutic strategies for the delivery of five types of RNAs (such as siRNA, miRNA, mRNA, circRNA, and lncRNA). The review was concluded with deliberations on the key challenges and future outlooks of exosome-loaded RNA applications for cancer therapy.

Nano-CaCO₃ powders are widely used in electronic ceramics, high-grade coatings and other fields. With the development of technology, higher requirements have been put forward for its particle size and dispersibility in applications. In this paper, we synthesized nano-CaCO₃ powders in one step using the sand milling-bubble carbonization method and explored the formation mechanism of monodisperse nano-CaCO₃. The results show that the particle size of Ca(OH)₂ has a significant effect on the particle size of CaCO₃. The sand milling during the carbonization process can effectively promote the dissolution of Ca(OH)₂ and, at the same time, effectively control the particle size and homogeneity of CaCO₃, thus obtaining CaCO₃ powders with refined grains and high dispersibility. Under the optimized process, by controlling the pre-sanding time of Ca(OH)₂ to 20 min and the Ca(OH)₂ concentration to 1.5 mol/L, pure calcite-phase CaCO₃ powder was achieved. The SEM average particle size was 60 ± 10 nm, the particle size distribution D₅₀ was 0.073 μm, and the equivalent diameter of the powder calculated by the specific surface area test was about 71 nm. These values were in good agreement with each other, indicating that the CaCO₃ powder is monodisperse. This study provides a simple and effective method for the large-scale preparation of monodisperse nano-CaCO₃ powders using industrial carbonization.